In recent years, thin client systems have been known in which a server apparatus manages resources, such as applications and files, so that functionality equipped in a client apparatus is reduced as much as possible.
In the thin client system, with a result of processing executed by the server apparatus and/or data held thereby being displayed on the client apparatus, the client behaves as if it were playing major roles of executing the processing and/or were holding the data.
One example of a method for task execution in such a client system is a method in which a server apparatus executes applications for document creation tasks, mail management tasks, and so on and a client apparatus displays results of the processing of the applications.
In recent years, in addition to such document creation tasks and mail management tasks, there have been demands for extensively applying tasks to be executed by thin client systems to, for example, high-definition-image handling tasks, such as a CAD (computer-aided design) creation tasks, and moving-image playback and edit tasks.
When a CPU (central processing unit) of a client apparatus executes a large-load task such as a CAD creation task or a moving-image-handling task, the amount of information transferred from the server apparatus to the client apparatus increases, which may delay responses to operations executed by the client apparatus. One known example of technologies for improving the response speed is a technology in which a display screen is divided into multiple blocks, a block in which the update frequency is high is detected from the blocks, and an image in the detected block is determined as a moving image and is read and transferred with high priority (e.g., Japanese Laid-open Patent Publication No. 11-275532).